Add py package as explicit dev dependency

It appears that this was previously a transitive dependency of
one of the other packages installed in the tox environment, but is
no longer (most likely due to the package being deprecated). This
plugin only depends on the package for mypy typing and for backward
compatibility with versions of PyTest prior to 7.0.

setup.cfg

@@ -45,6 +45,7 @@ dev =
     flake8
     flake8-quotes
     mypy
+    py>=1.9.0
     pytest-xdist>=2.0.0
     requests-mock[fixture]
     types-requests

src/pytest_unflakable/_plugin.py

@@ -10,7 +10,6 @@
 import logging
 import pprint
 
-import py
 import pytest
 import _pytest
 import sys
@@ -27,6 +26,7 @@
 )
 
 if TYPE_CHECKING:
+    import py
     from typing import Literal
 
     # Most of these types aren't defined or exported in older versions of pytest, but we only need
@@ -35,15 +35,16 @@
     CallPhase = Literal['setup', 'call', 'teardown']
     CollectReport = pytest.CollectReport
     Config = pytest.Config
+    PathCompat = Union[py.path.local, Path]
 else:
     CallInfo = object
     CallPhase = str
     CollectReport = object
     Config = object
+    PathCompat = object
 
 TestPathAndName = Tuple[str, Tuple[str, ...]]
 QuarantinedTests = Set[TestPathAndName]
-PathCompat = Union[py.path.local, Path]
 
 
 class QuarantineMode(Enum):